Michael DiBiccari, a senior at Hauppauge High School in Hauppauge, New York, has been working with NSLS biophysicist Elaine DiMasi. His project is part of a wider research effort on the study of biomineralization, the process by which living organisms produce minerals, such as shell and bone. He is studying diatoms -- single-celled algae with outer shells composed of biosilica, a type of biomineral.
DiBiccari has used x-rays to identify the atomic structure of the biosilica, which he then compared to the structure of synthetic silica. His results show that the structures of both materials are identical. He will discuss this research and its implications on Thursday, March 16, 2006, at 1:15 p.m. in Room 323 of the Baltimore Convention Center.
Samantha Palmaccio, also a student working with DiMasi, attends Sachem High School in Farmingville, New York. She is investigating the biomineralization of protein fibers, which is one step in the process by which many organisms form shells. Recently, she studied the "growth" of the mineral calcium carbonate on a protein-fiber network.
Her results show that the strength of the mineral increases over time as it covers the fibers. This is unlike stand-alone calcium carbonate. Additionally, using a powerful microscope, she was able to study the crystal structure formed by the mineral. Palmaccio will discuss her results on Monday, March 13, 2006, at 8:24 a.m. in Room 326 of the Baltimore Convention Center.
Additionally, two graduate students working at the NSLS will give talks on their research. Kathryn Krycka, from Stony Brook University, works with NSLS scientist and interim chair Chi-Chang Kao and Professor Sara Majetich of Carnegie Mellon University. Using an x-ray technique known as small-angle resonant x-ray scattering, she studies the size and internal structure of magnetic nanoparticles, which often consist of metal-only cores surrounded by thin metal-oxide shells. This work is important for understanding the magnetic properties of nanoparticle systems. In her talk, scheduled for March 14 at 9:24 a.m. in Room 319 of the Baltimore Convention Center, she will discuss her recent work on cobalt-oxide nanoparticles.
Raji Sundaramoorthy, a student of NSLS user scientist and collaborator Alex Weiss from the University of Texas at Arlington, is working with NSLS scientist Steve Hulbert. She has been studying photon-stimulated "Auger" decays in solids, a type of multi-electron decay. In this process, an incoming x-ray photon creates a "hole," or positively-charged electron vacancy, in one of the atom's core levels. The hole then is filled by an electron that jumps down from a higher electron orbital, which in turn causes an electron (the Auger electron) to be ejected from the solid. An Auger decay often results in a cascade of additional decays, leaving the atom ionized. At the NSLS, Sundaramoorthy has closely studied this process in the compound manganese oxide, and has compared her results to that of silver and palladium. She will discuss these results at 10:12 a.m. on March 13 in Baltimore Convention Center Room 311.
"The NSLS considers education to be an important part of its scientific program and mission," said Kao. "As is also evident by these talks, students at the NSLS are working on a wide range of exciting research topics."
These studies were supported by the Office of Basic Energy Sciences within the U.S. Department of Energy's Office of Science (1,2,3,4), the National Science Foundation (1,2,3), a Brookhaven Lab-Stony Brook University Seed Grant (1), and The Welch Foundation (2).
1: Palmaccio; 2: Sundaramoorthy; 3: Krycka; 4: DiBiccari
One of ten national laboratories overseen and primarily funded by the Office of Science of the U.S. Department of Energy (DOE), Brookhaven National Laboratory conducts research in the physical, biomedical, and environmental sciences, as well as in energy technologies and national security. Brookhaven Lab also builds and operates major scientific facilities available to university, industry, and government researchers. Brookhaven is operated and managed for DOE's Office of Science by Brookhaven Science Associates, a limited-liability company founded by the Research Foundation of State University of New York on behalf of Stony Brook University, the largest academic user of Laboratory facilities, and Battelle, a nonprofit, applied science and technology organization. Visit Brookhaven Lab's electronic newsroom for links, news archives, graphics, and more: http://www.bnl.gov/newsroom